package com.sjzl.util;

import java.security.MessageDigest;

/**
 * MD5加密
 * @author 黄健
 */
public class MD5Encrypt {

	/**
	 * 加密密匙
	 */
	private static final String KEY = ":cookie@huangjian325.com";

	public static String getKey() {
		return KEY;
	}

	/**
	 * MD5 加密算法
	 */
	public final static String calcMD5(String ss) {

		String s = ss == null ? "" : ss;

		char hexDigits[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
				'a', 'b', 'c', 'd', 'e', 'f' };
		try {
			byte[] strTemp = s.getBytes();
			MessageDigest mdTemp = MessageDigest.getInstance("MD5");
			mdTemp.update(strTemp);
			byte[] md = mdTemp.digest();
			int j = md.length;
			char str[] = new char[j * 2];
			int k = 0;
			for (int i = 0; i < j; i++) {
				byte byte0 = md[i];
				str[k++] = hexDigits[byte0 >>> 4 & 0xf];
				str[k++] = hexDigits[byte0 & 0xf];
			}
			return new String(str);
		} catch (Exception e) {
			return null;
		}
	}
	
}
